The trigeminal nerve is very closed to the SCA, AICA, PICA and the petrosal veins.As a result, about 46.88% of SCA has a point of contacting with the trigeminal nerve.

• 三叉神经和相关的小脑上动脉(SCA)、小脑前下动脉(AICA)、岩静脉等关系密切，小脑上动脉的行程一般比较恒定，向尾侧凸起46.；88%25的尾袢对三叉神经造成压迫。